COPD is characterized by airflow obstruction due to chronic bronchitis or emphysema. It a progressive disease with no known cure. Preferred treatment modalities include the adoption of healthy living habits to prevent further respiratory damage, pharmacotherapy, and surgery. The first improves the quality of life of the patient but is insufficient to reverse the course of the disease and does not provide relief in the long-term. The second, pharmacotherapy, is largely palliative, and no studies support even the proposition that even early drug intervention can significantly alter the course of COPD. And the third, surgery (i.e., lung volume reduction surgery, or LVRS), carries with it several risks even apart from those that attend any complicated thoracic surgery, though it is admittedly known to provide improvements in forced expiratory volume, a decreased total lung capacity, and improvement in lung function.
Improvements deriving from LVRS have led researchers to explore non-surgical methods of reducing total lung volume. The most well accepted approach has been to provide means of obstructing an airway to selected region or regions of the lungs to collapse a portion of a lung. The efficacy of an obstruction may be enhanced if it is placed permanently or semi-permanently.
Patents relating to methods and apparatus for such a procedure include: U.S. Pat. No. 6,258,100, to Alferness, et al, which discloses a method of collapsing a lung region by placing in an air passageway a plug which prevents air flow in both directions or a one-way valve which permits exhaled air to pass but precludes inhaled air from passing. The method shows the steps of inserting a conduit into the air passageway communicating with the lung portion to be collapsed; advancing an obstruction device down the conduit into the air passageway; deploying the obstruction device, thereby sealing the air passageway and causing it to collapse.
A second patent to Alferness, et al., namely, U.S. Pat. No. 6,293,951, shows a method and apparatus similar to that disclosed in the '100 patent, but further including a method and apparatus for pulling a vacuum within the lung portion for first collapsing the lung portion, and then, while the lung portion is collapsed, placing and deploying an obstruction device to maintain the lung portion in a permanently collapsed state.
U.S. Pat. No. 6,632,243, to Zadno-Azizi et al, teaches a method and apparatus for body fluid flow control in urinary, venous or pulmonic ducts or passageways. It includes the ability to seal about the device in the fluid passageway, a placement and retention format for the device, and a valve body capable of either or both a pressure threshold for operation and a one-way flow restriction. The valve body preferably has end bulk resilience and a passage through the valve body which is closed by that bulk resilience. One-way flow is produced by a flap or other inhibitor physically impeding flow in one direction or by a configuration of the valve to employ passage pressure to prevent opening.
U.S. Pat. No. 6,592,594, to Rimbaugh et al., discloses a method and apparatus for deploying a bronchial obstruction device in an air passageway, the system including a conduit configured for insertion into and down the trachea, into a bronchus communicating with the trachea, and then into the air passageway communicating with the lung portion. The system includes a capsule dimensioned to house the bronchial obstruction device and to be advanced down an internal lumen of the conduit into the air passageway. The capsule has a break-away distal end configured to release the bronchial obstruction device for deployment in the air passageway upon being pushed from the capsule by a pusher member.
U.S. Pat. No. 6,328,689, to Gonzalez, et al., teaches a lung constriction device, including a sleeve of elastic material, configured to cover at least a portion of a lung. The sleeve has a pair of opened ends to permit the lung portion to be drawn into the sleeve. Once drawn therein, the lung portion is constricted by the sleeve to provide air leak suppression and to reduce the size of the lung portion.
U.S. Pat. No. 6,679,264, to Deem et al., shows methods and apparatus for placing and deploying an air flow control element having a valve to prevent airflow in the inhalation direction but permit airflow in the exhalation direction. The flow control element is guided to and positioned at the site by a bronchoscope introduced into the patient's trachea and used to view the lungs during delivery of the flow control element. The valve may include one, two or more valve elements, and it may be collapsible for easier delivery. A source of vacuum or suction may be used to increase the amount of fluid withdrawn from the lung tissue.
U.S. Pat. Appl. No. 2003/0070682, to Wilson et al, teaches methods and devices for regulating fluid flow to and from a region of a patient's lung to achieve a desired fluid flow dynamic to a lung region during respiration and/or to induce collapse in one or more lung regions. A flow control device is implanted into a bronchial passageway. The flow control device includes a valve to regulate fluid flow, a seal partially surrounding the valve, and an anchor secured to the seal. The anchor exerts a radial force against an interior wall of the bronchial passageway to retain the flow control device in a fixed location in the bronchial passageway. The flow control device can either eliminate air flow into the targeted lung region or it can permit a regulated airflow to and from the targeted lung region to achieve an improved air flow dynamic that does not result in lung collapse. A delivery system is also disclosed. It includes a catheter having a proximal end and a distal end, and it is sized for insertion into a respiratory tract and deployed to a target location of a bronchial passageway through a trachea. A housing near the distal end of the catheter has an interior cavity that partially receives the flow control device. An ejection member is movably positioned in the housing and is mechanically coupled to an actuation device so that the flow control device can be ejected out of the housing.
U.S. Pat. No. 6,712,812, to Roschak et al, teaches for altering gaseous flow within a lung. The devices produce collateral openings or channels through the airway wall so that oxygen depleted/carbon dioxide rich air is able to pass directly out of the lung tissue to facilitate both the exchange of oxygen ultimately into the blood and/or to decompress hyper-inflated lungs.
Several more recent patents and/or patent applications disclose intra-bronchial valve devices and removable lung volume reduction devices. An especially prolific group collaborating in a very focused inventive enterprise for Spiration, Inc., of Seattle, Wash., have produced a series of interesting applications, notable among them: US Pat. Appl. Ser. Nos. 2003/0181922; US Pat. Appl. Ser. No. 2003/0195385; US Pat. Appl. Ser. No. 2003/0216769; US Pat. App. Ser. No. 2004/0143282; US Pat. Appl. Ser. No. 2004/0167636; US Pat. Appl. Ser. No. 2004/0243140; US Pat. Appl. Ser. No. 2005/0033310; and US Pat. Appl. Ser. No. 2005/0033344. While difficult to generalize about a large body of art, the foregoing collection all relate to removable anchored lung volume reduction devices employed and methods for using the devices.
The foregoing patents reflect the current state of the art of which the present inventor is aware. Reference to, and discussion of, these patents is intended to aid in discharging Applicant's acknowledged duty of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above-indicated patents disclose, teach, suggest, show, or otherwise render obvious, either singly or when considered in combination, the invention described and claimed herein.